Pivot support for miniature floated units



Jan. 8, 1963 w. E. TAYLOR 3,072,446

PIVOT SUPPORT FOR MINIATURE FLOATED UNITS Filed June 9, 1961 INVENTOR. WlLLIAM E. T YLOR BY Uw fizz. (2 45.

ATTORNEYS United States Patent PIVOT SUPPORT FOR MINIATURE FLOATED UNITS William E. Taylor, Oakland, N.J., assignor to the United States of America as represented by the Secretary of the Air Force Filed June 9, 1961, Ser. No. 116,211

5 Claims. (Cl. 308-59) and achieving the exacting alignment tolerances required is a very complicated one. In precision instruments of 7 this kind, it is important not only to have the critical parts in near perfect alignment, but also to provide a means of adjusting the axial freedom of the component and then locking it in place in the desired position of adjustment. In miniaturization of these components, these problems are made more acute by the small size of the elements and the lack of space. The method most commonly used to support the float is the one shown in FIG. 2 of the drawing. This illustration does not incorporate the features of the invention and is presented to show the state of the art. In this type of element, the pivot tip 10 is pressed into a holder or bearing in the element to be supported and consists of a straight section 12 and a threaded section14. A small screwdriver slot 13 in the screw fitted end makes possible the axial adjustment of the pivot member so that axial play of the floated component is provided for. Once the adjustment has been made, the pivot is locked in place by cement or other means.

While the method is seemingly satisfactory, it has many shortcomings. Experience has shown that it is practically impossible to machine a thread of the order this screwdriver slot almost invariably causes the formation of burrs and this greatly increases the danger of binding. Lastly, the method of locking the pivot makes any later adjustment impossible.

It is the object of the present invention to overcome all of these difficulties. The important advantages provide by the invention are:

(1) A pivot holder is provided which makes it relatively simple to achieve the close tolerances necessary for the proper performance of the unit.

(2) A rapid and reliable method of setting the end shake or allowable axial play of the float.

' (3) An automatic locking feature.

The straight shank of the original pivot has been retained but has been extended over the whole length of the pivot holder. The threads on this element have been completely eliminated.

In the drawing,

FIG. 1 is a vertical cross section of the device.

is of the order of FIG. 2 shows the state of the art which the present invention seeks to improve;

Referring more particularly to the drawing, the straight shank 12 of the pivot tip 10 shown in FIG. 2 has been retained as element 12 in the improved device. The element 12 may be referred to as a shank or pivot holder, its characteristic, as distinguished from the shank 12 of the prior art being a smooth surface uninterrupted by screw threads and capable of sliding engagement in the casing 16. It will be noted that the screw threads 14 of the original device have been eliminated and the surface of the shank presents a smooth surface. A device has been provided for retaining a smooth surface and, at the same time, preventing shank or pivot holder 12 from sliding out of the casing or other mounting element 16. The shank or pivot holder 12 is provided with a neck portion 18 of reduced diameter and a head 20 which may be an eccentric flange or rectangular block. Shims 32' can be inserted sideways over the neck portion 18 and turned to the position shown in FIG. 1. These shims can be introduced in the number necessary to provide spacing and axial adjustment of the shank 12. The head or flange 20 is uniquely arranged to prevent the escape of the shank 12 from the casing. A screw threaded member 22 engages in a. bore 24 in the casing 16. The bore 24 is axially parallel to and spaced from the bore which accommodates the smooth surfaced member 12. It is provided with a spacing element 26, and a knurled head 28 for adjustment. An anchoring element 30, which may be beryllium copper or comparable resilient material, is held between the head 28 and the spacer 26. This element is, in fact, a leaf spring and provides resiliency for adding or removing shims 32 while holding the pivot holder firmly in its bore.

Small horseshoe-shaped shims 32 are inserted under the flange 20. The number and size of the shims selected determine the position and degree of axial freedom of the float.

The simplification of the pivot has made it possible to attain the close tolerances necessary for the proper alignment of the pivot. Furthermore, the end shake setting, i.e. the experimentally determined proper position is antomatically locked by the leaf spring. The assembly of these parts and the final setting of the axial play are both simple procedures. The pivot is slipped into the microsyn and the leaf spring is assembled with its holddown screw. The thickness of the shims required varies only siightly from unit to unit and the initial shims can be selected so that very little subsequent change is needed. The float is moved back and forth in the axial direction and, by means of a dial indicator, the actual end shake or setting is determined. The final setting can thus be achieved by adding or subtracting shims. This operation can be completed in one, or at most two, steps.

While the invention is shown and described in connection with one form for illustrative, rather than restrictive purposes, it is obvious that changes and modifications may be made by those skilled in the art without departing from the scope and spirit of the invention as defined in the accompanying claims.

I claim:

1. A pivot. support for floated units comprising a casing, a smooth surfaced cylindrical pivot holder insertable in a smooth bore in said casing, a neck on said holder of smaller diameter than the diameter of said pivot holder, shims, selectable in number, and insertable on said neck for defining axial movement of said pivot holder, a flange attached to said neck of larger diameter than said bore, a screw threaded element insertable into a second bore in said casing in screw threaded relationship therewith, said first and second bores being spaced and axially paral- Patented Jan. 8, 1963 lel, a head on said screw threaded element, a spacing element on said screw threaded element, a leaf spring positioned between said spacing element and said head, said leaf spring extending over a portion of said flange to hold said pivot holder in said first-named bore for providing a governable pressure on said pivot holder.

2. A pivot support for a floated unit comprising a casing, a smooth surfaced pivot holder positioned in a bore in said casing, a flange on said pivot holder positioned on the exterior of said casing and of larger dimensions than the area of said bore, means for maintaining said pivot holder in said bore, said means comprising a leaf spring in anchoring position for anchoring said pivot holder, screw threaded means independent of said pivot holder for adjustably anchoring said leaf spring.

3. A pivot support comprising a slidably mounted pivot holder component, means for mounting said component in a casing to allow axial movement thereof, means for adjusting the axial freedom of said component and means for locking said component at a selected position of adjustment, said means for adjusting the axial freedom of said component comprising, a selected number of horseshoe shims insertable in a neck of said component, a screw threaded element mounted in said casing spaced from and independent of said pivot holder component and an anchoring element for exerting pressure on said 4 pivot holder component, said anchoring element being adjustable by means of said screw threaded element.

4. A pivot support comprising a casing, a pivot holder slidably mounted in a bore in said casing, 21 head on said pivot holder extending over a portion of the exterior of said casing, spacing shims selectively insertable between said head and said casing, means for anchoring said pivot holder in said casing, said means comprising a screw threaded element mounted in said casing spaced from and mounted independently of said pivot holder and capable of exerting anchoring pressure thereon.

5. A device for screw threadedly anchoring a slidably mounted microsyn pivot holder, said device comprising a pivot holder slidably mounted in a bore in the casing of said microsyn, a screw threaded element also mount- References Cited in the file of this patent UNITED STATES PATENTS Saal June 18, 1918 Sasse May 19, 1953 

1. A PIVOT SUPPORT FOR FLOATED UNITS COMPRISING A CASING, A SMOOTH SURFACED CYLINDRICAL PIVOT HOLDER INSERTABLE IN A SMOOTH BORE IN SAID CASING, A NECK ON SAID HOLDER OF SMALLER DIAMETER THAN THE DIAMETER OF SAID PIVOT HOLDER, SHIMS, SELECTABLE IN NUMBER, AND INSERTABLE ON SAID NECK FOR DEFINING AXIAL MOVEMENT OF SAID PIVOT HOLDER, A FLANGE ATTACHED TO SAID NECK OF LARGER DIAMETER THAN SAID BORE, A SCREW THREADED ELEMENT INSERTABLE INTO A SECOND BORE IN SAID CASING IN SCREW THREADED RELATIONSHIP THEREWITH, SAID FIRST AND SECOND BORES BEING SPACED AND AXIALLY PARALLEL, A HEAD ON SAID SCREW THREADED ELEMENT, A SPACING ELEMENT ON SAID SCREW THREADED ELEMENT, A LEAF SPRING POSITIONED BETWEEN SAID SPACING ELEMENT AND SAID HEAD, SAID LEAF SPRING EXTENDING OVER A PORTION OF SAID FLANGE TO HOLD SAID PIVOT HOLDER IN SAID FIRST-NAMED BORE FOR PROVIDING A GOVERNABLE PRESSURE ON SAID PIVOT HOLDER. 